【简介】
摘要：比较了几种RoHS常用的六价铬检测标准，考察了萃取时间和萃取剂对钢板涂镀层中六价铬含量测定结果的影响，阐述了各种六价铬萃取方法的适用性。实验表明，沸水萃取法适用于可溶性六价铬的萃取，弱碱苹取法可用于两性金属涂镀层。分析了目前钢板涂镀层表面六价铬检测方法中存在的问题，探讨了六价铬限制法规的符合性问题。
关键词：钢板；涂镀层；六价铬；测定；萃取；沸水；碱；RoHS指令
中图分类号：TGl78 文献标志码：A
文章编号：l004—227X(2009)02—0028—03
Comparison between the methods for determining hexavalent chromium in steeI sheet coatings／／CHEN Gui-lin+，KONG Ralene，QIAN Eric，ZHU Ping
Abstract：Some commonly．used standards for determining hexavalent chromium were compared．The effects of extraction time and extracting agent on the determination of hexavalent chromium content in coatings on steel sheets were studied．The applicability of individual method for extracting hexavalent chromium was expatiated．The experimental results showed that boiling water extraction is suitable for testing soluble hexavalent chromium compounds and weak alkaline extraction suitable for amphoteric metal coatings．The problems existing in present test methods for determination of hexavalent chromium in steel sheet coatings were analyzed．The compliance of RollS directive was discussed．
Keywords：steel sheet；coatin9；hexavalent chromium； determination；extraction；boiling water；alkaline；RollS directive
First．author’s address：Centre Testing International． Shenzhen 518101．
1 前言
欧盟RoHS指令(Directive 2002／95／EC The restriction of the use of certain hazardous substances in electrical and electronic equipment)以及中国的《电子信
息产品污染控制管理办法》(即中国RoHS)对电子产品中六价铬等6种有害物质作了限制规定。钢板在电子行业中广泛应用，传统的电镀和其他表面处理工艺，尤其是铬酸盐钝化，对环境产生巨大影响。为了满足各类法规的要求，企业积极开发无铬工艺，努力实现环保产品。但是，针对金属表面或涂镀层表面六价铬的测试方法目前尚无法统一，而且测试结果又难以满足RoHS指令对六价铬0．1％的限值要求。本文考察了目前使用较广的六价铬检测方法在测定钢板涂镀层表面六价铬时的差异性和适用性，以及影响测定的因素，并探讨了RoHS中金属涂镀层表面六价铬符合性问题。
